The present invention relates to a method and an apparatus for producing large-caliber ammunition including a combustible or partially combustible propelling charge casing and a compacted or partially compacted propelling charge powder. The present invention further relates to ammunition unit including a combustible or partially combustible propelling charge casing and a loose propelling charge which has been partially compacted according to the method of the invention.
Various methods are known in which, in order to increase the internal ballistic performance, the propelling charge powder is further compacted or compressed, either partially or completely, in a cartridge casing. The compaction or compression of the propelling charge powder is here always effected within a pressure resistant metal propelling charge casing or in some other, separate pressing device, with the compacted powder then being transferred into the propelling charge casing. It is here implicitly assumed that the material of the metal propelling charge casing or the other pressing device is suitable to withstand without deformation the radial pressure forces generated during the compaction or compression and acting perpendicular to the walls as well as the tangential friction forces (shear forces) acting parallel to its walls.
This is generally the case for propelling charge casings, projectile casings or other metal devices. For combustible or at least partially combustible propelling charge casings having, for example, non-combustible casing stubs or casing bottoms, the prior art propelling charge compaction methods cannot be employed due to the poor strength of the combustible material since the pressure forces perpendicular to the casing walls generated during the compaction or compression of the powder and the friction or shear forces also occurring during this process and acting parallel to the casing walls would destroy or at least deform the propelling charge casing to the extent that a cartridge stressed in such a way (enlargement of its diameter) could no longer be loaded into the weapon.